生物化学期末总复习资料(双语)

生物化学复习资料

Amino acid（氨基酸）: All proteins are made up from the same set of 20 standard amino acids. A typical amino acid has a primary amino group, a carboxyl group, a hydrogen atom and a side-chain(R group) attached to a central α-group atom(Cα). Proline（脯氨酸）is the exception to the rule in that it has a secondary amino group.

Primary structure（一级结构）: The linear（线状的）sequence of amino acids joined together by peptide bonds is termed（被称为）the primary structure of the protein. The position of covalent disulfide bonds between cysteine（半胱氨酸）residues is also included in the primary structure.

Secondary structure（二级结构）: Secondary structure is a protein refers to the regular folding of regions of the polypeptide chain. The two most common types of secondary structure are the αhelix and βpleated sheet（β折叠）.

Tertiary structure（三级结构）: Tertiary structure in a protein refers to the three-dimensional（三维的）arrangement of all the amino acids in the polypeptide chain. This biologically active, native conformation（构造；形态）is maintained by multiple（多重的；多样的）noncovalent （非共价的）bonds.

Quaternary structure（四级结构）: if a protein is made up of more than one polypeptide chain it is said to have quaternary structure. This refers to the spatial（空间的）arrangement of the polypeptide subunits（亚基；亚单位）and the nature of the interactions between them.

Protein stability（蛋白质稳定性）: In addition to the peptide bonds between individual amino acid residues, the three-dimensional structure of a protein is maintained by a combination of noncovalent interactions(electrostatic forces（静电力）, van derWaals forces（范德华力）,hydrogen bonds（氢键）, hydrophobic forces（疏水作用力）) and covalent interactions(disulfide bonds（二硫键）).

The Bohr effect(波尔效应): H+, CO2and 2,3-bisphosphoglycerate（2,3-二磷酸甘油酸）are allosteric effectors（变构效应剂）, promoting the release of O2 from hemoglobin（血红蛋白）. H+ and CO2 bind to different parts of the polypeptide chains, while 2,3-bisphosphoglycerate binds in the central cavity（凹穴）between the four subunits.

Dialysis（透析）: Proteins can be separated from small molecules by dialysis through a

semi-permeable membrane（半透膜）which has pores that allow small molecules to pass through but not proteins.

Function and diversity of collagen（胶原蛋白）: Collagen is the name given to a family of structurally related proteins that form strong insoluble（不可溶的）fibers. Collagens consist of three polypeptide chains, the identity and distribution of which vary between collagen types.

Gel filtration chromatography(凝胶过滤层析)

Ion exchange chromatography(离子交换层析)

Affinity chromatography(亲和层析)

Enzymes as catalysts（作为催化剂的酶）: Enzymes are catalysts（催化剂）that change the rate of a reaction without being changed themselves. Enzymes are highly specific and their activity can be regulated. Virtually all enzymes are proteins, although some catalytically active RNAs have been identified.

Active site（活性位点）: The active site is the region of the enzyme that binds the substrate, to form an enzyme-substrate complex, and transforms it into product. The active site is a three-dimensional entity（实体）, often a cleft（裂口）of crevice（缺口）on the surface of the protein, in which the substrate is bound by multiple weak interactions. Two models have been proposed to explain how an enzyme binds its substrate: the lock-and-key model and the induced-fit model（诱导契合模型）.

Enzyme classification（酶的分类）: Enzymes are classified into six major groups on the basis of the type of reaction that they catalyze. Each enzyme has a unique four-digit classification number.

Enzyme assays（酶的测定）: An enzyme assay measures the conversion of substrate to product, under conditions of cofactors, pH and temperature at which the enzyme is optimally active（最佳活性的）.

Coenzymes（辅酶）and prosthetic group（辅基）: Some enzymes require the presence of cofactors, small nonprotein units, to function. Cofactors may be inorganic ions or complex organic molecules called coenzymes. A cofactor that is covalently attached to the enzyme is called a prosthetic group. A holoenzyme is the catalytically active form of the enzyme with its cofactor, whereas an apoenzyme（脱辅基酶蛋白）is the protein part on its own.

Isoenzymes（同工酶）: Isoenzymes are different forms of an enzyme which catalyze the same reaction, but which exhibit different physical of kinetic（动力学的）properties（性质）.

Activation energy and transition state: For a biochemical reaction to proceed, the energy barrier